The present invention relates to systems and methods for improving plasma propellant ablation/sublimation based systems. In particular, embodiments can include improved methods and apparatuses associated with plasma pulsed thruster (PPT) including reduction of carbon charring during ablation of a carbon-fluorine polymer as well as increasing thrust, heat transfer, and ablation of the propellant.
Carbon-fluorine (C2F4)n based polymers can be used as a dielectric propellant material in different types of PPTs. In PPTs, an electrical potential difference can be applied between a cathode and anode separated by the dielectric propellant. Current flows across the surface of the propellant, ablating and sublimating the propellant. Heat can be generated by the potential difference causing the propellant to create plasma. The plasma is charged, and the propellant completes the circuit between the cathode and anode allowing current to flow through the plasma. The flow of electrons between the anode and cathode can generate a strong electromagnetic field, which can exert a Lorentz Force on the plasma. The plasma is accelerated away from the propellant due to the Lorentz force. Inspection of the PPT propellant surface after firing show signs of carbon charring and ablation near the electrodes, which can cause failure of the PPT due to a low energy-to-thruster radius ratio. This charring can be formed primarily from carbon, which can result in a carbon flux to be returned from the plasma rather than from the incomplete decomposition of the propellant.
According to an illustrative embodiment of the present disclosure, systems and methods for improving plasma propellant ablation/sublimation based systems are provided. One set of embodiments provides systems and methods for reducing carbon charring during plasma system (e.g., a plasma coating application system) propellant (e.g., a carbon-fluorine polymer) ablation and increasing heat transfer, ablation, and plasma thrust from plasma system. In particular, one embodiment can include using a nano or micro-sized magnetic or electromagnetic field responsive material as particulates or microcapsules that are intermixed with, e.g., polytetrafluoroethylene (e.g., Teflon®) nano-fibers, and using resulting fiber composites as the propellant material. Embodiments include improved plasma system, e.g., PPTs, plasma torch, plasma coating system, etc, as well as nozzle improvements such as embodiments with magnetic structures disposed in relation to the nozzle.
Additional features and advantages of the present invention will become apparent to those skilled in the art upon consideration of the following detailed description of the illustrative embodiment exemplifying the best mode of carrying out the invention as presently perceived.